I hunt Colorado, Michigan, Indiana, and Illinois. I wear wool, and really that's it. From the base layer to the outer layer. I guess I also have a down vest I utilize and a gortex shell for downpours, but that's it. It is fire resistant, warm when wet, water resistant, and when layered properly wind resistant. Plus it breaths. It is also naturally less apt to smell than synthetics. I am prone to getting cold, and sweat a lot. Still, I carry the layers and wear what I can manage, and I can stay warm very nicely. When I started hunting the mountains I started looking at things a lot differently, and carrying a little extra for a long hike seems like no extra effort now. It can all be perspective...